How to Polish Out Scratches on Laser Discs

by ke4mcl in Circuits > Lasers

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How to Polish Out Scratches on Laser Discs

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In this instructable I'm going to cover a process I've used to buff out scratches from laser discs. Before I get into the process I need to tell you that I'm in no way an optics engineer and this process has not been lab tested. Any long term effects it may have on the discs are unknown. There's plenty of ideas on how to do this task. I'm the tech at the Miami Space Transit Planetarium and we still use laser discs on a daily basis. This is just one way to get the scratches out that worked for me.

I tested this process on the workbench using discs that were blatantly scratched up and beginning to act up when played. If you have a disc that's almost at the point of being unplayable, this process might save the disc and make it playable again but by all means record that video ASAP to another media. This process may work on cd's and dvd's but I haven't tried that yet.


What You'll Need

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First off you need to clean the disc of any grease or grime. Once it's clean and dry we are ready to start. You will need to obtain two products, a small jar of "Mother's Mag and Wheel polish" and a bottle of plastic scratch remover. I have a few friends in the public safety business and they swear by Mother's Mag and Wheel polish when it comes to removing haze and light scratches in plastic lenses. Yes, wheel polish cleans up scratched plastic! Who would have thought to try that one out?

The second product, plastic scratch remover, is available at some auto parts stores and at boat stores. It's used for polishing up plastic windshields and so forth. The particular brand I used was "Star Brite Plastic Scratch Remover". This stuff looks and smells like watered down car wax. It may just be that in a special bottle. I haven't tried car wax but I imagine clear coat safe car wax :might: work the same.

You will also need 3 small CLEAN terry cloth towels. One big enough to lay the disc on while you work on it, and two to work in the compounds. These towels must be clean, as in right out of the washer and haven't been used for anything else clean. Now we'll get to work!

Wax On, Wax Off

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Lay the towel down on a flat surface and lay the disc on the towel. Open up the jar of Mother's and swab a little out with your finger tip (you did wash your hands before starting this process right?). Start working the compound onto the disc using small circular motions just as if you were washing a car. Obviously long fingernails are not conducive to this task. Use light pressure as you are doing this. You want to have enough compound to make it easy to work but don't lather it on the disc. Work your way all around the disc. It's very important you use circular polishing motions and not side to side. Allow it to dry for a few minutes and then take one of your terry cloth towels and start buffing. Once again use small circular motions. Once you've achieved a cloudy haze all around the disc move on to a clean part of the towel and re-buff till the disc shines. Don't forget to remove any compound that got on the edge of the disc or on the inner edge where the hole is. This process should have helped clear up some of the more pronounced scratches.

Now we're going to use the liquid scratch remover for the final polish. Clean your hands. Apply as per directions on bottle. Work liquid onto disc using same small circular buffing motions with fingertip. Allow to set for a few minutes. Buff out to a light haze with clean part of towel. Buff again to a shine with another clean part of towel. Lift disc up and clean up any compound that got on the edges or somehow worked its way under the disc.

Bask in the Shine

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Wallah! You're done.. on one side at least! If you have a two sided disc repeat the process for the other side but make sure you're not laying the freshly polished side on any globs of spilled compound. You may have some lint from the towel on the disc that can be gently blown off. Play and enjoy!